NASA’s Langley Research Center researchers developed DAMAS using an iterative algorithm to deconvolute noise signals, allowing for more accurate quantification of the position and strength of acoustic sources. Recent development of the DAMAS microphone phased array processing methodology allows the determination and separation of coherent and incoherent noise source distributions. The DAMAS technology represents a significant breakthrough in the field of aero-acoustics.
In 2004, NASA developed the DAMAS deconvolution approach for the mapping of acoustic sources that decoupled the array design and processing influence from the noise being measured using a simple and robust algorithm. DAMAS does not add any additional assumption to traditional array processing/integration analysis. It merely extracts the array characteristics from the source definition presentation. In 2005, three-dimensional applications of DAMAS were examined. DAMAS was shown to render an unambiguous quantitative determination of acoustic source position and strength.
The present development, called DAMAS-C, extends the basic approach to include coherence definition between noise sources. The solution incorporates cross-beamforming array measurements over the survey region. While the resulting inverse problem can be large and the iteration solution computationally demanding, DAMAS-C solves problems that no other technique can approach. DAMAS-C is validated using noise source simulations, and is applied to airframe flap noise test results.
This technology has numerous aerospace and transportation applications, including noise and vibration control, and general noise-source localization and quantification. It can also be used in instrumentation for music and environmental acoustics.